576 NEW YOEK STATE MUSEUM 



sive marslies near Randolph, and Conewango for example being- 

 underlain by clay tbrougliout their entire extent.'^ 



At Levant, 4: miles east of Jamestown, Cbantanqua co., is an 

 interesting bed of blue clay underlying an area of several acres. 

 It is probably of postglacial age, and the section as determined by 

 an artesian well-boring is: 



Yellow sand "4 feet 



Quicksand 4 inches 



Yellow clay 5 feet 



Blue clay 70 " 



Hardpan 



Total thickness 83 



a 



The owner of the clay bed informed me that leaves were often 

 found between the layers of the clay at a depth of 15 or 20 feet. 



At Breesport near Elmira there was a bank of blue clay rising 

 from the valley to a hight of 50 feet, but it represents the lens- 

 shaped type of clay deposit included in the moraine at many points, 

 and has been worked out. A similar deposit is found at IsTew- 

 field 6 miles south of Ithaca, where a moraine crosses the val- 

 ley, the clay forming a large portion of one of the morainal hills, 

 but surrounded by till. Deposits of clay suitable for brick and tile 

 occur extensively in the lowlands bordering the Mohawk river 

 from Home to Schenectady. The beds vary in thickness from 6 

 to 15 feet and are mostly of a red, blue, or gray color. 



Among the most extensive and important clay formations 

 occurring in New York are those of the Hudson valley.^ Here 

 are deposits of two types: 1) estuary deposits of fine stratified 

 sand, yellow and blue clay, and 2) cross-bedded delta deposits, 

 the materials of which are much coarser. The estuary deposits 

 indicate a period of depression, and deposition in quiet water. 



1 Geol. New York, 4th district. 1843. 



2 H. Ries, Rep't of N. T. state geologist, 1890. 



